The energy group said it had sent helicopters to take all non-essential crew off the installation, located 232 miles off the Scottish shore, on Tuesday.

Seventy people remain on board after 92 were removed and three experts brought in to help handle the leak.

Taqa stressed that oil had not spilled into the environment and is contained in the platform leg, but added that workers have not yet uncovered the source of the leak.

Oil levels at the platform are being monitored by the operator, which said it will focus "all our efforts on addressing this issue".

The closure is not expected to have any immediate impact on oil prices.

Anthony Lobo, head of energy at KPMG, said that the UK had sufficient oil inventories to last up to 30 days and therefore it would have taken more than a couple of weeks of the outage before the Brent oil price would have been affected.

Malcolm Graham-Wood, oil and gas advisor at VSA Capital, said: "If the market was in a difficult state, then something like this might affect the price, but in its own right, it won't.

"However, if the pipeline stays off for any length of time - in the order of months - then it will have an effect."

Professor Alex Kemp, an oil economist at Aberdeen University, told BBC Radio Scotland's Good Morning Scotland programme: "What we have is an incident which impacts on the Brent pricing system which is used as a marker price for a lot of the world's production.

"If it continues one would expect a limited affect on the Brent price.

"But the Brent price doesn't just depend on Brent production, it depends on production from a lot of other fields.

"The effect should be limited because although the Brent price is the marker for a huge volume of oil in the world market, Brent production constitutes not all that big a proportion of the total."